Chalk lines are highly visible straight lines drawn on relatively flat surfaces to allow a user to clearly mark the surface to provide visual cues for distance measurements, to designate borders, or for spatial orientation among others. The temporary nature of chalk allows lines to be drawn without permanently marking the surface and the low-cost of chalk allows the liberal use of chalk to create chalk lines. As a result, chalk lines are important in various industries as well as everyday life for the ability to provide low-cost, temporary markings.
Chalk lines are typically drawn using a handheld chalk line tool for smaller areas or with field chalk markers for larger areas. Handheld chalk line tools draw straight chalk lines by the use of a string coated with chalk. The string is laid across the surface to be marked and pulled taut. The string is then plucked, causing the string to strike the surface which transfers the chalk to the surface along the straight line. As a handheld tool the strings have a very small diameter and short length to allow portability, thereby limiting its use to smaller areas. Additionally, the string of the handheld chalk line tool is susceptible to breakage and to moisture which affects the ability of the string to retain the proper amount of chalk to create a visible line. To overcome the shortfalls of the handheld chalk line tool, larger field chalk markers are used.
The field chalk markers typically include a hopper with a controllable dispenser mounted on a frame with wheels. The hopper is filled with chalk and as a user pushes the field chalk marker along a relatively flat surface, the dispenser dispenses the chalk onto the surface thereby creating a line. In order to adequately apply the chalk to the surface, the dispenser is placed as close as possible to the surface to prevent the chalk from being displaced by external forces such as wind. On uneven surfaces, the limited clearance between the dispenser and the surface becomes a problem as the dispenser may contact the uneven surface making it difficult to move the field chalk marker. Further, the wheels of the field chalk marker contacts and moves along the surface making the field chalk marker susceptible to surface changes. The various angles, heights, depths, and obstructions from an uneven surface, such as a construction zone, will veer the field chalk marker off-course and greatly hinder the field chalk marker from creating straight, visible chalk lines.
In light of the disadvantages of existing chalk line tools and field chalk markers, it would be advantageous to provide a handheld chalk line tool utilizing existing low-cost chalk to create straight lines on all types of terrain. It would be further advantageous to provide a handheld chalk line tool which does not contact the surface. It would be further advantageous to provide a handheld chalk line tool capable of quickly changing the width of the chalk line. It would be further advantageous to provide a handheld chalk line tool having an ergonomic handle positioning the center of gravity along the central axis of the hopper to reduce user fatigue.